scholarly journals Inhibition of steroid 5α-reductase by specific aliphatic unsaturated fatty acids

1992 ◽  
Vol 285 (2) ◽  
pp. 557-562 ◽  
Author(s):  
T Liang ◽  
S Liao

Human or rat microsomal 5 alpha-reductase activity, as measured by enzymic conversion of testosterone into 5 alpha-dihydrotestosterone or by binding of a competitive inhibitor, [3H]17 beta-NN-diethulcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one ([3H]4-MA) to the reductase, is inhibited by low concentrations (less than 10 microM) of certain polyunsaturated fatty acids. The relative inhibitory potencies of unsaturated fatty acids are, in decreasing order: gamma-linolenic acid greater than cis-4,7,10,13,16,19-docosahexaenoic acid = cis-6,9,12,15-octatetraenoic acid = arachidonic acid = alpha-linolenic acid greater than linoleic acid greater than palmitoleic acid greater than oleic acid greater than myristoleic acid. Other unsaturated fatty acids such as undecylenic acid, erucic acid and nervonic acid, are inactive. The methyl esters and alcohol analogues of these compounds, glycerols, phospholipids, saturated fatty acids, retinoids and carotenes were inactive even at 0.2 mM. The results of the binding assay and the enzymic assay correlated well except for elaidic acid and linolelaidic acid, the trans isomers of oleic acid and linoleic acid respectively, which were much less active than their cis isomers in the binding assay but were as potent in the enzymic assay. gamma-Linolenic acid had no effect on the activities of two other rat liver microsomal enzymes: NADH:menadione reductase and glucuronosyl transferase. gamma-Linolenic acid, the most potent inhibitor tested, decreased the Vmax. and increased Km values of substrates, NADPH and testosterone, and promoted dissociation of [3H]4-MA from the microsomal reductase. gamma-Linolenic acid, but not the corresponding saturated fatty acid (stearic acid), inhibited the 5 alpha-reductase activity, but not the 17 beta-dehydrogenase activity, of human prostate cancer cells in culture. These results suggest that unsaturated fatty acids may play an important role in regulating androgen action in target cells.

2017 ◽  
Vol 83 (9) ◽  
Author(s):  
Woo-Ri Kang ◽  
Min-Ju Seo ◽  
Kyung-Chul Shin ◽  
Jin-Byung Park ◽  
Deok-Kun Oh

ABSTRACT Oleate hydratases (OhyAs) catalyze the conversion of unsaturated fatty acids to 10-hydroxy fatty acids, which are used as precursors of important industrial compounds, including lactones and ω-hydroxycarboxylic and α,ω-dicarboxylic acids. The genes encoding OhyA and a putative fatty acid hydratase in Stenotrophomonas maltophilia were identified by genomic analysis. The putative fatty acid hydratase was purified and identified as an oleate hydratase (OhyA2) based on its substrate specificity. The activity of OhyA2 as a holoenzyme was not affected by adding cofactors, whereas the activity of the original oleate hydratase (OhyA1) showed an increase. Thus, all characterized OhyAs were categorized as either OhyA1 or OhyA2 based on the activities of holoenzymes upon adding cofactors, which were determined by the type of the fourth conserved amino acid of flavin adenine dinucleotide (FAD)-binding motif. The hydration activities of S. maltophilia OhyA2 toward unsaturated fatty acids, including oleic acid, palmitoleic acid, linoleic acid, α-linolenic acid, and γ-linolenic acid, were greater than those of OhyA1. Moreover, the specific activity of S. maltophilia OhyA2 toward unsaturated fatty acids, with the exception of γ-linolenic acid, was the highest among all reported OhyAs. IMPORTANCE All characterized OhyAs were categorized as OhyA1s or OhyA2s based on the different properties of the reported and newly identified holo-OhyAs in S. maltophilia upon the addition of cofactors. OhyA2s showed higher activities toward polyunsaturated fatty acids (PUFAs), including linoleic acid, α-linolenic acid, and γ-linolenic acid, than those of OhyA1s. This suggests that OhyA2s can be used more effectively to convert plant oils to 10-hydroxy fatty acids because plant oils contain not only oleic acid but also PUFAs. The hydration activity of the newly identified OhyA2 from S. maltophilia toward oleic acid was the highest among the activity levels reported so far. Therefore, this enzyme is an efficient biocatalyst for the conversion of plant oils to 10-hydroxy fatty acids, which can be further converted to important industrial materials.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2713 ◽  
Author(s):  
Mayakrishnan Prabakaran ◽  
Kyoung-Jin Lee ◽  
Yeonju An ◽  
Chang Kwon ◽  
Soyeon Kim ◽  
...  

Soybeans are low in saturated fat and a rich source of protein, dietary fiber, and isoflavone; however, their nutritional shelf life is yet to be established. This study evaluated the change in the stability and quality of fatty acids in raw and roasted soybean flour under different storage temperatures and durations. In both types of soybean flour, the fatty-acid content was the highest in the order of linoleic acid (18-carbon chain with two double bonds; C18:2), oleic acid (C18:1), palmitic acid (C16:0), linolenic acid (18:3), and stearic acid (C18:0), which represented 47%, 26%, 12%, 9%, and 4% of the total fatty-acid content, respectively. The major unsaturated fatty acids of raw soybean flour—oleic acid, linoleic acid, and linolenic acid—decreased by 30.0%, 94.4%, and 97.7%, and 38.0%, 94.8%, and 98.0% when stored in polyethylene and polypropylene film, respectively, after 48 weeks of storage under high-temperature conditions. These values were later increased due to hydrolysis. This study presents the changes in composition and content of two soybean flour types and the changes in quality and stability of fatty acids in response to storage temperature and duration. This study shows the influence of storage conditions and temperature on the nutritional quality which is least affected by packing material.


Author(s):  
Mei Isnaeni ◽  
O R Faidiban ◽  
Angelina Novita Tethool

Red fruit oil is a red fruit extraction product (Pandanus conoideus Lam) containing a lot of antioxidants such as carotenoids, tocopherols as well as unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid and decanoic acid which is potential to be used as an additive for semen chicken diluents. This study aims to obtain an information about the effectiveness of adding red fruit oil as a cement diluent derived from male native chickens. The treatment consisted of 0.9 ml ringer laktat + 0.1 ml semen (Pl), ringer laktat 0.98 ml + 0.1 ml semen + 0.02 ml red fruit oil (P2), ringer laktat 0.96 ml + 0.1 ml semen + 0.04 ml red fruit oil (P3),  ringer laktat 0.94 ml + 0.1 ml cement + 0.06 ml red fruit oil (P4). The results showed the sperm motility ranged from 48.17 ± 7.86%  to 84.67 ± 2.42%. Treatment P1 and P2 have a very significant difference (P <0.01) on motility 0.05). The spermatozoa concentration ranged from 1,600x106 cells / ml to 2,200x106 cells/ml. The spermatozoa concentration of treatment P1 and P2 chickens did not show any significant differences (P> 0.05), nor did among treatments P2, P3 and P4.  However, treatment P1 has a significant difference on spermatozoa concentration with P3 and P4. (P <0.05). It can be concluded that the addition of red fruit oil in lactated ringer diluent can be used as an additive for semen diluents because it is able to maintain the concentration. In addition, adding of red fruit oil  up to concentrations of more than 2% tend to reduce sperm motility. Keywords: Concentration, Motility, Spermatozoa and Red fruit oil


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lihong Ma ◽  
Xinqi Cheng ◽  
Chuan Wang ◽  
Xinyu Zhang ◽  
Fei Xue ◽  
...  

Abstract Background Cottonseed is one of the major sources of vegetable oil. Analysis of the dynamic changes of fatty acid components and the genes regulating the composition of fatty acids of cottonseed oil is of great significance for understanding the biological processes underlying biosynthesis of fatty acids and for genetic improving the oil nutritional qualities. Results In this study, we investigated the dynamic relationship of 13 fatty acid components at 12 developmental time points of cottonseed (Gossypium hirsutum L.) and generated cottonseed transcriptome of the 12 time points. At 5–15 day post anthesis (DPA), the contents of polyunsaturated linolenic acid (C18:3n-3) and saturated stearic acid (C18:0) were higher, while linoleic acid (C18:2n-6) was mainly synthesized after 15 DPA. Using 5 DPA as a reference, 15,647 non-redundant differentially expressed genes were identified in 10–60 DPA cottonseed. Co-expression gene network analysis identified six modules containing 3275 genes significantly associated with middle-late seed developmental stages and enriched with genes related to the linoleic acid metabolic pathway and α-linolenic acid metabolism. Genes (Gh_D03G0588 and Gh_A02G1788) encoding stearoyl-ACP desaturase were identified as hub genes and significantly up-regulated at 25 DPA. They seemed to play a decisive role in determining the ratio of saturated fatty acids to unsaturated fatty acids. FAD2 genes (Gh_A13G1850 and Gh_D13G2238) were highly expressed at 25–50 DPA, eventually leading to the high content of C18:2n-6 in cottonseed. The content of C18:3n-3 was significantly decreased from 5 DPA (7.44%) to 25 DPA (0.11%) and correlated with the expression characteristics of Gh_A09G0848 and Gh_D09G0870. Conclusions These results contribute to our understanding on the relationship between the accumulation pattern of fatty acid components and the expression characteristics of key genes involved in fatty acid biosynthesis during the entire period of cottonseed development.


Author(s):  
Vilcacundo E ◽  
Alvarez M ◽  
Silva M ◽  
Carpio C ◽  
Morales D ◽  
...  

 Objective: The aim of this study was to determine the fatty acids composition in a tocte seeds oil (Juglans neotropica Diels) sample cultivated in Ecuador.Methods: Tocte oil was obtained from tocte seeds using the cold pressing method. Fatty acids analysis was carried out using the gas chromatography method with a mass selective detector (GC/MSD) and using the database Library NIST14.L to identify the compounds.Results: Methyl esters fatty acids were identified from tocte (J. neotropica Diels) walnut using the GC–MS analytical method. The total lipid content of tocte walnuts seeds of plants cultivated in Ecuador was of 49.01% of the total lipid content on fresh weight. Fatty acids were analyzed as methyl esters on a capillary column DB-WAX 122-7062 with a good separation of palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. The structure of methyl esters fatty acids was determined using the GC–MS. Tocte walnut presents 5.05% of palmitic acid, 2.26% of stearic acid, 19.50% of oleic acid, 65.81% of linoleic acid, and 2.79% linolenic acid of the total content of fatty acids in tocte oil. Fatty acids content reported in this study were similar to the data reported for other walnuts seeds.Conclusions: Tocte seeds are a good source of monounsaturated and polyunsaturated fatty acids. Tocte oil content oleic acid and with a good content of ɷ6 α-linoleic and ɷ3 α-linolenic. Tocte walnut can help reduce risk cardiovascular diseases in Ecuador for their good composition of fatty acids.


1977 ◽  
Vol 55 (16) ◽  
pp. 2159-2167 ◽  
Author(s):  
Yolande Dalpé ◽  
Peterjürgen Neumann

The unsaturated fatty acids oleic, linoleic, and linolenic induce the formation of the imperfect state of fructification of the Graphium type (coremia) with Ceratocystis ulmi and C. piceae and the Leptographium type with C. penicillata. Intraspecific difference between several strains of C. ulmi show that linoleic acid is the best inducer with an optimal concentration from 0.05 to 0.20 g/ml of methanol between the 10th and 25th day of culture. Linoleic and linolenic acid extend the capacity of sporulation of C. penicillata, conserving the strains capability of differentiation of Leptographium structures when ordinarily only the natural substrate can reinduce it. Ceratocystis dryocoetidis cultivated in the same conditions remains insensible to the lipid treatments.


2021 ◽  
Vol 3 (4) ◽  
pp. 19-24
Author(s):  
Asya Çetinkaya

In this study, it was aimed to determine the effect of some production parameters on the characteristics of butters made from whey, which is an important dairy by-product, and creams obtained from milk. The acidity values of milk, whey, cream, and butter were respectively detected as 0.17±0.00%, 0.13±0.01%, 0.22±0.01%, 0.24±0.01%, 0.26±0.00%, 0.25±0.01%, fat values were respectively detected as; 3.50±0.14%, 0.60±0.19%, 39.0±0.34%, 43.0±0.35%, 80.0±0.46%, 84.0±0.42% and protein values were respectively detected as; 3.30±0.19%, 0.68±0.03%, 0.93±0.12%, 0.54±0.03%, 0.51±0.02%, 0.58±0.00%. 10 saturated and 7 unsaturated fatty acids were detected in cream and whey butter samples. It was seen that the most common fatty acids were palmitic, stearic, myristic and oleic acid, and the amount of oleic, stearic and linoleic acid was higher in whey butter. In conclusion, we can state that whey, which is an important dairy residue, can be used as an alternative raw material in butter production.


2014 ◽  
Vol 139 (4) ◽  
pp. 433-441 ◽  
Author(s):  
Geoffrey Meru ◽  
Cecilia McGregor

Seed oil percentage (SOP) and fatty acid composition of watermelon (Citrullus lanatus) seeds are important traits in Africa, the Middle East, and Asia where the seeds provide a significant source of nutrition and income. Oil yield from watermelon seed exceeds 50% (w/w) and is high in unsaturated fatty acids, a profile comparable to that of sunflower (Helianthus annuus) and soybean (Glycine max) oil. As a result of novel non-food uses of plant-derived oils, there is an increasing need for more sources of vegetable oil. To improve the nutritive value of watermelon seed and position watermelon as a potential oil crop, it is critical to understand the genetic factors associated with SOP and fatty acid composition. Although the fatty acid composition of watermelon seed is well documented, the underlying genetic basis has not yet been studied. Therefore, the current study aimed to elucidate the quality of watermelon seed oil and identify genomic regions and candidate genes associated with fatty acid composition. Seed from an F2 population developed from a cross between an egusi type (PI 560023), known for its high SOP, and Strain II (PI 279261) was phenotyped for palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), and linoleic acid (18:2). Significant (P < 0.05) correlations were found between palmitic and oleic acid (0.24), palmitic and linoleic acid (–0.37), stearic and linoleic acid (–0.21), and oleic and linoleic acid (–0.92). A total of eight quantitative trait loci (QTL) were associated with fatty acid composition with a QTL for oleic and linoleic acid colocalizing on chromosome (Chr) 6. Eighty genes involved in fatty biosynthesis including those modulating the ratio of saturated and unsaturated fatty acids were identified from the functionally annotated genes on the watermelon draft genome. Several fatty acid biosynthesis genes were found within and in close proximity to the QTL identified in this study. A gene (Cla013264) homolog to fatty acid elongase (FAE) was found within the 1.5-likelihood-odds (LOD) interval of the QTL for palmitic acid (R2 = 7.6%) on Chr 2, whereas Cla008157, a homolog to omega-3-fatty acid desaturase and Cla008263, a homolog to FAE, were identified within the 1.5-LOD interval of the QTL for palmitic acid (R2 = 24.7%) on Chr 3. In addition, the QTL for palmitic acid on Chr 3 was located ≈0.60 Mbp from Cla002633, a gene homolog to fatty acyl- [acyl carrier protein (ACP)] thioesterase B. A gene (Cla009335) homolog to ACP was found within the flanking markers of the QTL for oleic acid (R2 = 17.9%) and linoleic acid (R2 = 21.5%) on Chr 6, whereas Cla010780, a gene homolog to acyl-ACP desaturase was located within the QTL for stearic acid (R2 = 10.2%) on Chr 7. On Chr 8, another gene (Cla013862) homolog to acyl-ACP desaturase was found within the 1.5-LOD interval of the QTL for oleic acid (R2 = 13.5%). The genes identified in this study are possible candidates for the development of functional markers for application in marker-assisted selection for fatty acid composition in watermelon seed. To the best of our knowledge, this is the first study that aimed to elucidate genetic control of the fatty acid composition of watermelon seed.


2016 ◽  
Vol 69 (4) ◽  
Author(s):  
Józef Klocek ◽  
Magdalena Szwed ◽  
Danuta Koczkodaj ◽  
Joanna Mitrus ◽  
Marian Saniewski ◽  
...  

The effect of methyl jasmonate (MJ) vapors on the composition and peroxidation of major fatty acids in the organs of common buckwheat seedlings was investigated. The composition of fatty acids in the hypocotyl and cotyledons of seedlings changed significantly under exposure to MJ vapors in closed jars. Four-day exposure to MJ led to a significant reduction in the concentrations of stearic, linoleic, and linolenic acids in the hypocotyl, whereas oleic acid levels increased approximately 3.5-fold. A decrease in stearic acid levels and an increase in the content of linolenic acid were noted in cotyledons, whereas oleic acid levels decreased in roots. Seven-day exposure to MJ vapor caused a further reduction in stearic acid content and an increase in oleic acid and linoleic acid levels in the hypocotyl. At the same time, the linoleic acid content of roots and linolenic acid levels in cotyledons were doubled, but a 5-fold reduction in linolenic acid concentrations was observed in roots. Methyl jasmonate intensified fatty acid peroxidation in cotyledons after 4 and 7 days and in roots after 4 days of exposure. Peroxidation was inhibited in the hypocotyl and roots after 7 days. The noted changes in the composition and peroxidation of fatty acids are probably indicative of senescence in buckwheat seedlings under the influence of MJ. Senescence seems to proceed faster in cotyledons than in other organs of buckwheat seedlings.


HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 1082D-1082 ◽  
Author(s):  
Kyoung-Shim Cho ◽  
Hyun-Ju Kim ◽  
Jae-Ho Lee ◽  
Jung-Hoon Kang ◽  
Young-Sang Lee

Fatty acid is known as a physiologically active compound, and its composition in rice may affect human health in countries where rice is the major diet. The fatty acid composition in brown rice of 120 Korean native cultivars was determined by one-step extraction/methylation method and GC. The average composition of 9 detectable fatty acids in tested rice cultivars were as followings: myristic acid; 0.6%, palmitic acid; 21.2%, stearic acid; 1.8%, oleic acid; 36.5%, linoleic acid; 36.3%, linolenic acid; 1.7%, arachidic acid; 0.5%, behenic acid; 0.4%, and lignoceric acid; 0.9%. Major fatty acids were palmitic, oleic and linoleic acid, which composed around 94%. The rice cultivar with the highest linolenic acid was cv. Jonajo (2.1%), and cvs. Pochoenjangmebye and Sandudo showed the highest composition of palmitic (23.4%) and oleic acid (44.8%), respectively. Cultivar Pochuenjangmebye exhitibed the highest composition of saturated fatty acid (28.1%), while cvs. Sandudo and Modo showed the highest mono-unsaturated (44.8%) and poly-unsaturated (42.4%) fatty acid composition, respectively. The oleic acid showed negative correlation with palmitic and linoleic acid, while positive correlation between behenic and lignoceric acids was observed.


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